Towards appropriate design criteria for roads in develop-ing countries.

Unit construction and fuel consumption costs per kilometer are presented conceptually as functions of the total rise and fall, in volumes, through a given terrain type.It is suggested that as the non-oil producing developing countries in particular, seek to reduce both initial construction costs and future vehicle operating costs, especially fuel consumption, they might best be advised to develop, individually, new design charts, such as the one suggested in this paper.